This invention relates generally to apparatus for retaining printed circuit (i.e., PC) boards in an electrical chassis or housing, and, more particularly, to retainer apparatus mounted along one edge of a PC board, for retaining the board in a narrow channel of the housing.
Retainer apparatus of this particular kind have been in common use for quite some time. The apparatus is typically attached directly to a side edge of a PC board, and the board and apparatus are inserted as a unit into a narrow slot or channel defined in a wall of the housing. Typically, two such retainer apparatus are used, each mounted on an opposite side edge of the board and received within a separate channel in the housing.
In most cases, the retainer apparatus has an effective thickness in a direction perpendicular to the plane of the PC board that can be selectively increased. After the board and retainer apparatus have been slidably inserted into the housing channel, the retainer apparatus is adjusted so as to increase its effective thickness and thus bear against one side wall of the channel. This, in turn, presses the opposite side of the PC board against the other side wall of the channel, to clamp the PC board in place.
Many retainer apparatus of this kind have included an assembly of wedge elements arranged end to end, with abutting walls that are sloped relative to the assembly's longitudinal axis. Rotation of a screw interconnecting the wedge elements draws them together, to increase the assembly's effective width and, thereby, retain the PC board in place.
Other retainer apparatus of this kind have included a rod, of generally oval cross section, mounted along one side edge of the PC board and rotatable about its longitudinal axis. The PC board and rod are slid into the housing channel with the rod oriented such that its relatively narrow width is directed perpendicular to the plane of the board. The rod thereafter can be rotated by one-quarter turn, to bring its relatively wide width into an orientation perpendicular to the board's plane. The rod then bears against an array of leaf springs positioned between the rod and one side wall of the housing channel, to retain the PC board in place.
The PC board frequently carries a multi-pin electrical connector adapted for coupling to a mating connector carried by the housing. The connector carried by the board is usually located on the board's leading edge, as it is slid into the two housing channels. In the past, the coupling of these mating connectors has been accomplished in a procedure completely separate from the retaining procedure described above. In particular, this coupling has been achieved, for example, by simply manually pushing the PC board's connector into engagement with the housing connector. In other circumstances, the connector elements have been engaged with each other using a helical guide fastener of a kind that includes a stud with a laterally projecting pin sized to be received by a receptacle having a helical channel. Rotating the stud causes it and the PC board to be moved in a direction along the stud's longitudinal axis, to couple together the two electrical connectors.
Although the retainer apparatus and the electrical coupling apparatus described above have each proven to be generally effective, it is believed that the overall combination is unduly complicated and difficult to operate. There is a need for a single, unified apparatus that can be used effectively to accomplish both functions, i.e., to retain a PC board in place while simultaneously coupling together mating electrical connectors. The present invention fulfills this need.